Applicant in the above-mentioned copending U.S. patent application Ser. No. 09/482,570 (the contents of which are incorporated herein by reference) has described a load power control system particularly suited for supplying electric power to banks of luminaires (street lamps). The contents of that application are incorporated herein by reference. That system, while well suited to controlling the power supplied to banks of luminaires, would be perceived by many as being too expensive and elaborate for economic use with a single HID-type luminaire. A simpler and less expensive design approach is desirable.
Ballast circuits for single luminaires are well known, and include both a constant-wattage category and a reactor category of ballast circuits. There is a need for a simple power control circuit for use with each category.